The present invention relates to medical pads, and more particularly, to medical pads utilized for thermal energy exchange with a patient. The invention is particularly apt pads utilized on the back region of a patient.
Increasingly, medical pads are being employed to achieve thermal exchange with patients. For example, medical pads have been widely employed to address emergency hypothermia or hyperthermia patient conditions. More recently, it has also been recognized that medical pads may be employed in conjunction with surgical procedures where selected thermal regulation of a patient is desired. For example, in procedures involving the exposure of bodily organs selective heating of the patient may be desirable.
To achieve thermal regulation in many medical pad systems, a heated or cooled fluid (e.g. air or water) is circulated through one or more pads which are contacted with a patient to affect surface-to-surface thermal energy exchange. As may be appreciated, the effectiveness of such thermal exchange is partially dependent upon the extent and intimacy of skin contact. In this regard, the establishment of the desired skin interface can be compromised where medical pads extend across bodily portions of differing complex configurations.
Additionally, the effectiveness of thermal exchange is partially dependant upon the maintenance of a desired thermal gradient across the medical pad-to-patient thermal exchange interface. In this regard, it should be noted that the maintenance of a predetermined rate of fluid circulation through the pad across the intended thermal exchange interface is important to achieving the desired thermal gradient.
In view of the foregoing, a primary objective of the present invention is to provide a medical thermal energy exchange pad that provides for enhanced maintenance of a desired thermal gradient across a pad-to-patient thermal exchange interface.
An additional objective of the present invention is to provide a medical thermal energy exchange pad that provides for an improved interface across bodily portions of different complex configurations.
It is further objective of the present invention to provide a medical thermal exchange pad that accommodates patient comfort during use.
Yet another objective of the present invention is to provide a medical thermal exchange pad that is relatively easy for medical personnel to utilize, that enhances fluid circulation reliability, and that otherwise reduces potential obstructions to patient medical care.
One or more of the above objectives and additional advantages are realized by the medical thermal exchange pad of the present invention. The inventive pad includes a pliable fluid containing layer for containing a fluid circulated from a first port to a second port of the fluid containing layer. The inventive pad further includes at least a first plurality of adjacent fluid channels, disposed within the fluid containing layer, wherein the first plurality of adjacent fluid channels have first coincidental configurations. The provision of multiple channels of coincidental configurations facilitates the maintenance of a desired thermal gradient across the pad-to-patient interface, e.g. since any patient pressure occlusion within the fluid containing layer can be localized and fluid flow shunting can be minimized.
In one aspect of the inventive pad, the first plurality of fluid channels may have coincidental, serpentine configurations. Further, the pad may include a second plurality of adjacent fluid channels within the fluid containing layer. In conjunction with such aspect, the second plurality of fluid channels may have second coincidental configurations different than said coincidental, serpentine configurations of the first plurality of fluid channels. The provision of at least two different sets of fluid channels having corresponding coincidental configurations which are different enhances the ability to adapt the pad to conform to bodily portions of differing complex configurations, while also providing for a highly reliable and efficient degree of thermal exchange with a patient.
In another aspect, the inventive pad may include a second plurality of adjacent fluid channels, wherein the first and second plurality of fluid channels are disposed in series for the passage of fluid therethrough between the first and second ports of the fluid containing layer. In conjunction with this aspect, the inventive pad may further include intermediate fluid staging chamber for receiving fluid from one of the first and second plurality of fluid channels and distributing such fluid into the other of the first and second plurality of fluid channels. For such purposes, the first and second plurality of fluid channels may each have ends which terminate at the intermediate fluid staging chamber. Such an arrangement further facilitates the provision of a relatively even fluid flow through the various regions of the medical pad.
In an additional aspect, the inventive pad may include a central segment and first and second side flap segments that are separately and pivotably interconnected to the central segment. In one arrangement, the end flap segment is pivotable about a pivot axis that is transverse to pivot axes of the side flap segments (e.g. at an angle of between about 70xc2x0 to 110xc2x0). Further, the first plurality of fluid channels may be disposed so that each of the channels include a U-shaped portion located in one of the first and second side flap segments. Such segmentation and channeling features further facilitate the ability to achieve conformal positioning of the inventive pad on bodily portions having differing complex configurations.
In yet a further aspect, the fluid containing layer of the inventive pad may include a central segment, at least one side flap segment pivotably interconnected to a central segment, and at least one end flap segment pivotably interconnected to the central segment. Additionally, the first and second ports of the fluid containing layer may be advantageously disposed within the end flap segment. Such positioning of the ports facilitates pad positioning on a patient, the ready establishment and maintenance of open fluid interconnections, and the localization of potential obstructions to medical personnel attending a patient. Further, the end flap segment may be pivoted relative to the central segment of the fluid containing layer so as to dispose the first and second ports away from bodily regions that may contact a patient support surface during medical procedures, thereby enhancing client comfort.
As will be appreciated, the various above-noted aspects of the present invention may be employed in various combinations. Further, additional related features may be employed with such aspects and combinations thereof.
In particular, the noted first plurality of channels may be of a substantially 1common length, e.g. within about 15% of an average length thereof, as measured along their respective center paths. Similarly, each of the first plurality of channels may also have a substantially common average width, e.g. within about 25% of an average of their average widths. Similarly, where a second plurality of channels are included, such channels may be of a substantially common length, e.g. within about 15% of an average length thereof, as measured along their respective center paths. The second plurality of channels may also have a substantially common average width, e.g. within about 25% of an average of their average widths. As may be appreciated, the provision of substantially common lengths within each channel set yields a substantially equal pressure drop from one end to the other of each of the channels comprising a given set. Further, the provision of substantially common widths further equalizes pressure drops and reduces flow shunting.
Where a first and a second plurality of channels are included in the inventive pad, one of the channel sets may be provided within an average channel width that is significantly greater than an average channel width of the other set. For example, the average width of a first plurality of channels may be established to be at least 5 times greater, and preferably between about 10 to 25 times greater than an average channel width of a second plurality of channels.
In a further feature, the inventive pad may be provided with fluid ports that are oriented to extend laterally away from a central segment. Additionally, such ports may be elongated and oriented to extend in substantially parallel co-relation. Such port orientation features can be implemented to reduce fluid line blockage considerations and facilitate patient access/comfort. Further, the ports may be provided with port members that are tapered to facilitate fluid flow and further enhance patient comfort.
The above-noted features of the present invention are particularly apt for implementation in medical thermal exchange back pads. In particular, a pair of back pads may be provided having central segments adapted for positioning on the right and left sides of a patient""s spine. Such an approach facilitates use of the pads on a wide range of patient sizes, and accommodates sequential positioning of the pads on a prone patient (e.g. by rolling the patient onto one shoulder then the other). The pads may further include a plurality of side flap segments that may be pivotably positioned relative to the central segments to accommodate positioning across the shoulder region, rib-cage region and/or back-to-hip/buttocks region of a patient. Additionally, a top end flap segment may be provided for pivotable positioning from the scapula to top shoulder region of a patient.
In one back pad embodiment, each of the back pads may be provided with fluid ports disposed in the corresponding end flap segments. More particularly, such ports may be of an elongated configuration and may be oriented to extend away from a patient, e.g. substantially parallel to the pivot axes corresponding with the end flap segments.
To facilitate securement of the back pads to a patient, an adhesive surface may be provided across one side of the pads. Preferably, such adhesive surface extends across a majority and preferably all of the patient-facing side of the pad. The adhesive surface may be advantageously defined by a conformable, thermally-conductive layer (e.g. a hydrogel layer). Further, adhesive strips with removable liners may be disposed along the outer side edges of the side flap segments and the top edge of the end flap segments of the pads. As may be appreciated, the liners on such adhesive strips may be selectively removed in conjunction with the liners provided on the above-noted conformable layer during positioning of the pads.
In addition to the noted features, the inventive pad may incorporate various teachings of U.S. Pat. No. 6,197,045 entitled xe2x80x9cCOOLING/HEATING PAD AND SYSTEMxe2x80x9d, and U.S. patent application Ser. No. 09/476,850 entitled xe2x80x9cCOOLING/HEATING PAD AND SYSTEMxe2x80x9d, filed Jan. 3, 2000, each hereby incorporated by reference in its entirety.
Additional aspects and advantages of the present invention will become apparent to those skilled in the art upon consideration of the further description provided hereinbelow.